NORTH BAY (KTVU) - Teams with cadaver dogs began a grim search Thursday for more dead in parts of California wine country devastated by wildfires, resorting in some cases to serial numbers stamped on medical implants to identify remains that turned up in the charred ruins.

New deaths confirmed Thursday took the toll to 31, making this the deadliest week of wildfires in California history.

Many of the flames still burned out of control, and the fires grew to more than 300 square miles (777 square kilometers), an area as large as New York City.

As new developments come into the newsroom we updating our fire coverage below:

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Napa County

The city of Calistoga in Napa County received a mandatory evacuation order Thursday because of the 22 wildfires raging through Northern California as wineries began to assess their damage and officials tried to get a handle on how many people were displaced from their homes.

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Sonoma County

The latest mandatory evacuation order was issued at 3:20 p.m. Friday. Sonoma County Sheriff's Office is issuing a mandatory evacuation north of Hwy 128 from Geysers Rd to Chalk Hill Rd. If you are in this are you need to evacuate now due to fire.

The Sonoma County Sheriff's Office had issued a mandatory evacuation order for the following area:

North of East Napa St from 4th Street East to end of E. Napa Street.

The area of 7th Street East, Castle Road, and Lovall Valley Road east of Old Winery Road is already in a Mandatory evacuation area. Shortly after noon a mandatory evacuation order had been issued for the area of East of 4th Street East, between Brazil and E. Napa Street and North of E. Napa Street, Between 4th Street East and Old Winery Road.

For more information on the fire, please call the hotline at 707-565-3856.

Sheriff Robert Giordano urged that once people are safe, to please contact their families and let them know where they are. He said he understood how frustrating it was for people who couldn't return to their homes because of the wildfires raging around Northern California and Santa Rosa, but he said it just wasn't safe.

He said 14 people in Sonoma County have died and they are working on identifying the victims, which could be a long process.

Authorities say just about anything could have started any one of the wildfires now tearing through Northern California. They say anything from a carelessly discarded cigarette, a downed power line, a car's backfire or a chainsaw's pull could all be a possible ignition source.

The wildfires in the North Bay area are creating what air quality managers are calling the worst air quality ever recorded for smoke. The Bay Area Air Quality Management District issued a smoke and spare the air advisory through Wednesday. Air quality managers recommend using a N95 mask with a filtration.